Police will take no further action against TV cook Nigella Lawson after she told a court that she had taken drugs, Scotland Yard has said.

The Metropolitan Police said a specialist team had examined all the evidence relating to the 53-year-old's confessions during the fraud trial of her two former assistants, but has concluded there will be no further action.

Self-styled domestic goddess Ms Lawson revealed during the trial of Elisabetta and Francesca Grillo that she took Class A drug cocaine with her late husband John Diamond when he found out he had terminal cancer, and in July 2010 when she claimed she was being ''subjected to intimate terrorism'' by her former husband, Charles Saatchi.

In a statement, Scotland Yard said there were "serious public interest concerns" about the message a prosecution would send to potential witnesses and victims in the future, and could deter people from being candid with police and the court.

It said: "The decision has been taken based on a number of factors, including the need for police action to be proportionate, whether further action would be in the public interest, and after consultation with the Crown Prosecution Service.

" There are serious public interest concerns about the message any prosecution would send out to potential witnesses and victims in the future.

"Whilst witnesses clearly cannot simply admit to any offence under oath without consequences, this has to be balanced with the requirement for victims and witnesses to tell the truth.

"Further police activity may deter victims from being candid with police and in court for fear of future investigation."

During the trial of the Grillo sisters last year, Ms Lawson told jurors at Isleworth Crown Court that she had tried cocaine, but said the idea that she was a habitual user of the Class A drug was ridiculous.

The TV star said she was ''not proud'' but would rather be ''honest and ash amed'' about what she had done.

She also admitted that she began taking cannabis in the last year of her marriage to multi-millionaire Mr Saatchi.

Mr Saatchi claimed in an email that Ms Lawson's drug use meant she allowed their former assistants to spend what they liked.

The message said: ''Of course now the Grillos will get off on the basis that you... were so off your head on drugs that you allowed the sisters to spend whatever they liked and, yes, I believe every word they have said.''

Police announced in December that a specialist team would examine the evidence a s part of a review into the matter.